Field of the Invention
The present invention relates to an image forming apparatus which uses an electrophotographic technique and a cartridge capable of being detachably attached to the image forming apparatus.
Description of the Related Art
In an image forming operation of an image forming apparatus which uses an electrophotographic technique, first, a photosensitive drum is uniformly charged by a charging roller. Moreover, the charged photosensitive drum is selectively exposed by an exposure device, whereby an electrostatic latent image is formed on the photosensitive drum. The electrostatic latent image formed on the photosensitive drum is developed by a developing apparatus as a toner image.
Moreover, the toner image formed on the photosensitive drum is transferred to a sheet by a transfer roller. The toner image transferred to the sheet is pressurized and heated by a fixing device whereby the toner image is fixed to the sheet. The image forming apparatus forms an image on the sheet in this manner.
In the image forming apparatus, in general, replenishment of toner and maintenance of means for forming an image on the sheet (process means) or the like are required.
In recent years, in order to perform such maintenance and the like easily, the photosensitive drum, the charging roller, the developing apparatus, and the like are integrated as a cartridge. A cartridge in which the photosensitive drum and the like are integrated is called a process cartridge and is detachably attached to an image forming apparatus body.
In such a cartridge, electrical terminals (cartridge-side terminals) for supplying voltage to process means such as the charging roller are provided. In a state in which the cartridge is attached to the image forming apparatus body, the cartridge-side terminals are electrically connected to electrical terminals (body-side terminals) provided on the image forming apparatus body. Here, when a foreign material adheres to the cartridge-side terminal, an electrical connection state between the cartridge and the image forming apparatus body may become unstable.
Thus, a configuration in which a shutter for covering the cartridge-side terminals is provided in a cartridge is proposed (Japanese Patent Application Publication No. 2005-128469). In a state in which the cartridge is detached from an image forming apparatus body, the shutter covers the cartridge-side terminals. Moreover, the shutter rotates in synchronization with an operation of attaching the cartridge to the image forming apparatus body whereby the shutter exposes the cartridge-side terminals.
However, in this configuration, since it is necessary to provide a mechanism for rotating the shutter in the cartridge, the number of components that form the cartridge increases. In addition, the increase in the number of components increases the cost of manufacturing the cartridge.